Tips on Using a Dictionary


A Latin dictionary may be a useful supplement to give a more complete picture of a word.  It can provide examples of the range of meanings of a word, particular idioms, whether verbs are transitive or intransitive, special cases used with a word, etymological information and information about related words, and complete principal parts or other forms.  It may also be helpful in distinguishing synonyms; for this, the English to Latin section is sometimes more helpful.

Skim the “Introduction,” “Advice to Readers” or similar section.  There should also be a list of abbreviations for reference when in doubt.
Some common abbreviations are:

  • cf.  (confer)  = compare
  • vi.  intransitive verb (no direct object)
  • tr./vt.    transitive verb (direct object required)
  • names of authors and works cited for quotations (see front of dictionary)



I can’t find a word where it should be in the dictionary. Why?

There are some variations in spelling.  Different dictionaries adopt different editorial policies.  Some common causes of confusion:
Does the word begin with consonantal “i” (followed by a vowel) (or in the middle between two vowels)? Some dictionaries spell these with a “j.”

  • e.g. adjuvō = adiuvō;    jam = iam

Note: double “i”: in compounds, “iaciō” becomes “-iiciō” by vowel weakening (see Linguistic Rules);  sometimes the “i” is kept double and sometimes it is simplified to a single “i”.

  • e.g. adiiciō or adiciō

N.B.  The same thing may happen with consonantal “u.”  Some dictionaries spell these with “u”; some spell them with “v.”

  • e.g.  uideō  = videō.

[Note:  The Romans used all capital letters, so the original was actually “V” for both the vowel and consonant.  The emperor Claudius tried to introduce the use of a different letter to distinguish these, but was unsuccessful in his time.]

Does the word have a set of double letters near the beginning or a prefix?
Sometimes a letter is changed to match a following letter (“assimilation”); this is especially true with the prefixes, particularly ad-.  Some dictionaries use only the assimilated forms, others use some unassimilated forms.    Dictionaries usually cross-reference at the beginning of the letter combination, but not always.  Here are some common prefixes that sometimes assimilate:

  • ad-   e.g. ad-ferō or af-ferō
  • con-  (together; completely)  com-moveō;  col-ligō
  • ē-/ex-  e.g. ex-ferō or ef-ferō

Does the word begin with ex(s)-? When the prefix ex- is added to words that begin with s-, some dictionaries use the spelling without the s-, and some include it.  E.g. ex-sistō may be under existō or exsistō; ex-spectō may be under expectō or exspectō.

Definitions for adverbs or participles (verbal adjectives) are sometimes given at the end of the entry for the word they were formed from.

  • lentē: listed at the end of the entry for the adjective lentus, -a, -um
  • parātus: listed at the end of the entry for the verb parō

Why are some long vowels marked but not others?

Some dictionaries do not include macrons (long vowel marks) for forms that follow the regular rules (e.g. genitive singular –ī; infinitive –āre)
Some dictionaries also include short vowel marks for certain vowels;  these marks are not normally included in written text editions.

Hyphens usually mark syllable divisions, but that doesn’t seem right here. What is going on?

Syllable divisions in Latin follow regular rules, so the hyphens in dictionaries are not used to mark syllable divisions.  They are used instead to mark the parts of the word that change.  In the first complete form of a word, the hyphen separates the part that stays the same, usually the base, from the ending.  The following forms sharing the same first part are not written out in full.  Only the ending or part that is different is written (with a hyphen);  this ending replaces the ending on the complete form after the hyphen.

  • mensa/ mens-a, -ae (= mensae)
  • capiō/cap-iō, -ere  (= capere)
  • magn-us, -a, -um (= magnus, magna, magnum)
  • pul-cher, -chra, -chrum

Why do some verbs only have two principal parts in some dictionaries?

Some dictionaries just give the first form and the infinitive for first, second, or fourth conjugation verbs with regular principal parts.

Why does the fourth principal part look different in different dictionaries?

The fourth principal part is listed in various ways.  The fourth principal part is usually the perfect passive participle; however, intransitive verbs do not have a passive form.  They may form supines (verbal nouns) and future active participle based on the same stem.  Some dictionaries give the supine form (-um) for all verbs.  Other dictionaries give the perfect passive participle (masculine nominative singular -us) for transitive verbs and the future active participle (nominative singular masculine -ūrus) for intransitive verbs.

Why aren’t the accented syllables marked?

Latin follows regular rules for the accentuation of words, so accents do not need to be marked.

Why can’t I just use/learn the first definition given? Isn’t that the most important?

Definitions are arranged in different ways in different dictionaries.  They are often not arranged in order of frequency; sometimes they are arranged chronologically or by etymological development  (usually concrete then more abstract).

  • legō, -ere  to collect, gather together, pick
  • trans.
    1. to pass through, traverse
    2. to survey, scan esp. [ecially] of writing, to read, peruse

The first definition given is not necessarily the best meaning for a particular passage.  Part of learning vocabulary is learning the range of meanings and uses of words.  Words do not always have a one-to-one correspondence with a word in another language.

  • dēbeō, -ēre  owe (+ DO); ought (+ infinitive)
  • dē (+ abl.)  down from [concrete: physical movement],
    • from [e.g. a group];
    • about, concerning  (> French “of”)

What is all the stuff in parentheses after the word and what use is it?

Etymological information (about the origin and history of the word) is often given in parentheses after the lexical entry.  This may indicate the root word or words that a word comes from;  this may be helpful in remembering or analyzing the meaning of a word.  For basic words not derived from other words, the entry may include comparative cognate words from other languages.  If there is just a word written in Greek letters in parentheses, it indicates that the Latin word was borrowed from Greek.  See the beginning of the dictionary for explanation of the symbols and abbreviations used.

  • princeps, principis  (primus/capio)  [Thus, it is the person who “takes the first [place]”: leader, prince, chief; also used for what was later called emperor]
  • comes, comitis (cum/eo)  [i.e. a person who “goes with” one, a companion, comrade, associate)

How do I know what construction or case a word takes?

Some words take different cases or constructions for people vs. things.  These are usually indicated using aliquis/aliquem, etc./homō for a person in the examples and aliquid/res/rem for a thing, with the case of the form indicating the case to be used.

  • tollō: to lift up, raise; elevate . . . aliquem [someone = person in the accusative case] in crucem, to crucify

Some useful Latin dictionaries

Traupman’s The New College Latin & English Dictionary
(includes notation of transitive vs. intransitive verbs)

Cassell’s New Latin Dictionary, e.g. Simpson.
Pickler REF:  PA 2365.L3.C3.1960
(hardcover; generally useful, especially for word roots)

Lewis and Short, A Latin Dictionary. (Oxford: Oxford UP, 1980=1879)  REF: PA 2365.E5.A7.1879
(complete; best for later Latin)

The Oxford Latin Dictionary (OLD) (Oxford: Oxford UP, 1990). REF:  PA 2365.E509
(complete; newest; not as useful for Medieval Latin since it does not go as late as Lewis and Short)

Dictionary of Medieval Latin from British Sources.  (Oxford: Oxford UP, 1989)

Niermeyer, J.F.  Mediae Latinitatis Lexicon Minus.  (Leiden:  E.J. Brill, 1954) on-line **

Stelten, Leo F.  Dictionary of Ecclesiastical Latin.  (Peabody, Mass: Hendrickson, 1995)  PA 2891.D53 1995)